Machine tool for bar stock



Jul-3125, 1939. ENADEUN 2,167,308

MACHINE TOOL FOR BAR STOCK Filed June 10, 1958 5 Sheets-Sheet 1 In ven tor.

B Wade/m y M %MM Ailor'neys.

5 Sheets-Sheet 2 Filed June 10, 1938 Jul 25, 1939.

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MACHINE TOOL FOR BAR STOCK filed June 10, 1938 :5 Sheets-Sheet 3 21 j I O l1 u w m v ]V J/ PH 1 2a a; 2 I

3 54 O0 [m/enlar; 26 0 0 0 0 O h8g6 0 O O O \O July 25, 1939. E. "NI'RDELIN 2,167,308

' MACHINE TOOL FOR BAR STOCK Filed June 10, 1958 5 Sheets-Sheet 4 In vemor y Aflorn y July 25 1939. E. NADELIN ,1

MACHINE TOOL FOR BAR STOCK Filed June 10, 1938 5 SheetsSheet- 5 In ventog Atlorneys,

/ZMM M Patented July 25, 1939 UNITED STATES .PATENT- OFFICE 2,167,308 moms 'roonron BAR s'roox many Application June 10, 1938, Serial No. 213,041

Germany June 12,. 1937 I 7 Claims.

My invention relates to machine tools, and more It is an object of my invention to improve a machine tool of this type, with a view to increasing the number of tooling operations under the control.

;To this end, in combination with a plurality of tooling units, I provide a control which is operatively connected to all'tooling units, means such as a lug on a ratchet wheel for adjusting the control for a predetermined number of machining operations on each bar in each unit, and mechanism which is influenced by the length of the bars being machined, for placing the control in active position.

By these means, a much greater number of tooling operations can be performed on a bar than with the control alone. The adjusting means, normally a lug on a ratchet wheel form ing part of the control, is so adjusted that bea tween the initial position of the control, and the presenting of a fresh bar at a tooling unit, the control is operated at least as many times as cutting operations are performed on the bar after it has been delivered to the tooling station.

In the accompanying drawings two machines embodying my invention are illustrated more or less diagrammatically by way of example.

In the drawings Figs. 1 to '7, inclusive, illustrate a machine with an indexed rotary stock reel for feeding the bar stock to the tooling units.

I 2 Figs. 8 and 9 illustrate a machine without the stock reel. 2

More particularly-- Fig. 1 is an elevation of the machine equipped with the stock reel.

Fig. la is a section on the line Ia-Ia in Fig. 1. Fig. 2 is a side elevation of the machine, viewed from the right'in Fig. 1 and partly in section on the line 11-11 in that figure. Figure 3 is an elevation of the stock reel. Fig. 4 is a section on the line IVIV.in Fig. 3. Fig. 5 is a section on the line V--V in Fig. 2.

, Fig. 6 is a detail showing that portion of the machine which is just below the stock reel, drawn to a larger scale.

' Fig. '7 is a section on the line VII V'.[I in Fig. 2.

Fig. 8 is an elevation showing the upper portion of the machine without the stock reel, 55 Fig. 9 is a planview of its table,

Referring now to the drawings, and first to Figs. 1 to 7, this machine is equipped with a central shaft I about whose axis its stock reel rotates. The stock reel, as best seen in Figs. 3 and 4, comprises a top plate 2 l with a circular row of 5 holes 24, Fig. 3a, an intermediate plate 22, with notches 23 in its perimeter, Fig. 3b, and a base plate 20, with holes 24a. arranged like the holes 24 in the top plate. The three plates are keyed on the shaft l. Tubes 2 are arranged to be inl serted in the holes 24 and 24a and in the notches. 23, and are equipped with annular abutments at their lower ends which bear on the base plate 20. The intermediate plate 22 is merely a brac- 15 I ing member.

Keyed on the shaft I! below the base plate 20 is a distributing disk 26, with a circular row of holes 21 in axial alignment below the holes 24a. in the base plate 20, and a flap 28 arranged to normally cover each hole 28. The flaps, two of which only are shown, are pivoted at 29 and equipped with springs, not shown, normally holding them against checks 28a, in which position they are above the corresponding hole 21. In the position illustrated in Fig. 4, however, the two diametrally opposite flaps are engaged by checks 3! at their outer ends, or tails, 30, and their inner ends are moved so as to expose the corresponding hole 21. The checks '35 are secured to an annular table I00 below the distributing disk 26, by brackets 31, as shown in Fig. 1.

An indexing plate M, with crown teeth 15, is arranged below the distributor 26, and a ball bearing la. supports the lower end of the shaft lagainst the control shaft bearing 82 at the upper end of the machine frame A. The annular table I00 is secured to the upper end of the frame A by suitable arms and surrounds the indexing plate 14 with a clearance. A bearing on the table I00 supports a pulley I2 on which is placed a cord, or cable, II, with its upper end secured in a groove in the perimeter of the disk 26, and a weight 13 at its lower end. The weight turns the disk 26 in the direction of the arrow in Fig. 4, unless it is retained by a tooth 18 on a detent 16 which is fulcrumed on the frame A at 11.

The machine is equipped with two tooling units, B1 at the right, and B2 at the left, Fig. 1, in the example illustrated, it being understood that more than two units may be provided, if

' desired. Since the units are quite similar, only .the unit B1 will be described, the corresponding parts in the unit B2 being distinguished by the index l 1 Each unit has a hollow shaft, 3 in the unit B1,

whose radial distance from the shaft l is equal to the radius of the circular row of holes 24a. in the base plate 20, and 21 in the distributor 26. The shaft 3 is driven by a double rope pulley 3" between an upper bearing 4 and a lower bearing for the shaft. A motor 46 is arrangedin the base A of the machine and a pulley 61 is keyed on its shaft. A rope or cable 61a is placed about the pulley 61, a pair of vertical pulleys 68 and Hi, the double pulleys 3" and 3" on the shafts 3 and 3', respectively, and a horizontal pulley 69 intermediate the two vertical pulleys. e purpose of this one-sided and comparatively complicated arrangement is to remove the belt 614; from the central portion of the machine where the space is occupied by other parts.

At its lower end the hollowshaft 3 is equipped with a chuck for engaging the bar stock delivered to it from the cage, as will be described, so that each bar rotates with thehollow shaft. The chucks have not been illustrated in detail as they may be of any suitable type. A sleeve [1, with a groove Ila, is mounted to slide on the upper end of each shaft, and is connected to the corresponding chuck by any suitable means, not shown. A pair of pins 88 in a chuck-control lever 33 engage in the groove lia of the sleeve W. The lever, at one end, is fulcrumed on a pin 34 which is supported by a spring 35 at the free end of a bracket 36' which is secured on the lower bearing 4 of the shaft 3. A connecting rod 3? is pivoted to the free end of the lever 33 and, with a slot 39, engages a pin 38 on a crank disk 40. A similar crank disk 40, with a pin 38', is provided for the unit B2.. The crank disks are keyed on the opposite ends of a. shaft 42' which ismounted to rotate in bearings, not shown, on the frame A. A bevel gear 42 is mounted to rotate on the shaft 42, and rotation is imparted to the bevel gear by means which will presently be described. A clutch-sleeve M" is splined on the shaft 42' for connecting the bevel gear 42 to the shaft. A spring, not shown, tends w throw out the clutch. For throwing in the clutch against theaction of its spring, a forkshaped lever 4| is secured on a shaft 41" which is mounted to turn in a bearing 31'. The bearing is connected to the frame A by a rib, as best seen in Fig. 2. A clutch-operating crank 31 is also keyed on the fork shaft 4 and is operated by a cable 48, as will be des ribed. When the clutch 4'!" has been thrown in by pins 4! at the ends of the forked arms M engaging in a groove in the sleeve 4!", the spring is compressed and the shaft 42' is rotated through one revolution, at the end of which the clutch is thrown out automatically by a cam or the like, and is returned into its inactive position by its spring.

Clutches of this kind are old in the art, and so this v one needs no detailed description. 'A sprocket 44 is connectedto the bevel gear 43, and is rotated from the shaft of the motor 46 through a chain-and-sprocket mechanism l28a, spur gears I28, a shaft 45a, and a sprocket 45 on the shaft. 4

To the free end of the crankfll is connected 2. cable 48. The other end of the cable extends to one arm of a double-armed horizontal lever 59 which is fulcrumed on the frame A at 49a over a pulley 48', as best seen in Fig. 1a. The other arm of the double-armed lever is equipped with an adjustable abutment 49b. The reaction of the clutch spring against the throwing-in of the clutch exerts tension on the cable 48 and holds the free end of the abutment 43b against the front end' of a slide! which supports the cutter 8 for the unit B1.

A pair of inclined guides 6, 6' are formed on the frame A. The carriage I, with its cutter 8,

is mounted to slide on the guide 6, and a similar slide I, with a cutter 8, is mounted to slide on the other guide 6'. Reciprocation is imparted to the slide I by a mechanism illustrated in Fig. 2, it being understood that an exactly similar mechanism, not shown, is provided for the slide I.

A cam shaft I4a, with a cam l4 at one end,

' and a cam M at the other end, is mounted below the shaft 450. in the base A of the frame A and is rotated by a worm 45b on the shaft 45, and a worm gear 450 on the cam shaft. A sprocket 45d on the cam shaft is connected to a sprocket 45c on a shaft Ma at one side of the frame A by a placed on the lower arm 53a for varying the stroke of the carriage I, the cammingmember being held against turning-and fixed in position on the arm 53a by a nut 65. An angular arm 33 is pivoted at 52 with its upper end, connected to the pivot 53b by a link 94 near its bend, and connected to a. link 96 at its free lower end. The free-end of the link 96 is slotted and engages -over a pin 96a on the lower arm 53a. A compression spring 63 is inserted between the nut 65 and a screw 64 in the angular arm 93. position illustrated, the lower arm is free to turn clockwise against the pressure of the .spring 63.

Arranged below, and in line with, the hollow shaft 3 of the unit B1 is a mandrel ID, with a. tapered member Illa at its upper end. The mandrel II! is pivoted to a slidell at I la, and a sleeve lib is placed over the joint to keep the parts straight. The lower end of the slide H is supported by a spring l2 on a 'camming member I3 which cooperates with the cam l4 and, in the position illustrated in Fig.2, is just about to be engaged by the descending portion of the eccentric o.

The mandrelsare mounted to slide in troughs l5 and i5, respectively. The hole for the mandrel'is surrounded by an elevated flange, and a cap "5 protects the lower portion of the slide against chips. The severed ends of the bars are delivered to a chute 55a, with a perforated bottom b allowing oil to fiow into the trough l5, and the chute delivers the ends to a collector 15c.

Arranged below the chuck I9 is a retainer slide 32. The slide has a toothedmember 50, with two teeth adapted to be engaged alternately by the free end of a pawl 5| whose other end is fulcrumed to the upper end of the upper arm 53. The pawl 5| obviously partakes in the oscillation of the arm 53 as it reciprocates the slide or carriage I. When the carriage performs its forward stroke the slide 32 is forced backagainst the action of a. return spring 55 and is locked in this position by a tooth 51a. on a pawl 51 engaging in a recess 56a in the'upper end ofan extension 56 at the rear of the slide 32. The pawl 51- is fulcrumed at 59 and its outer end is connected to the outer end of the extension by a spring 58.

Inthe A push rod 89 whose upper'end is arranged to cooperate with the crown teeth 15 of the indexing plate 14, is pivotally connected to the inner end of the pawl 51 at its lower end.

The control will now be described.- The control includes the shaft 42' on which the bevel gear 42 is unted, and certain parts making up a timing ed to rotate in the bearing 82 already referred to. On that end of the shaft which is in the vicinity of the right-hand unit. B1, is keyed a timing wheel 8| which is here constructed as a ratchet wheel, and on the opposite end is keyed a pulley 83 to which is connected the upper end of a belt 84. The belt rests on a pulley 84a and r at its lower end supports a weight 85 tending to turn the ratchet wheel in the direction of the arrow 10, Fig. 2. -A lug 88 is adjustably secured on the ratchet wheel 8| for cooperation with a hook 19 at one end of the detent 16. The sides of the hook and of the lug are shaped like edges, and the lug is free toyield toward the left in Fig. 2, so that the tooth 18 immediately engages in the next gap of the indexing plate 14. In order to prevent skipping of a gap by the tooth 18, the longer arm 16a of the detent 18 is crooked at right angles, and the lower end of the crooked portion bears on the tail of a retaining pawl 81 which is urged in upward direction by a compression spring 81a on the bracket 36. Theretaining pawl is fulcrumed on the frame A at 81b and atooth 86 at its upper end engages between the teeth of the ratchet wheel 8|. A lug 88 on the push rod 89 bears against the tail of the pawl-81 from above. Mounted to turn freely about the control shaft 8Ia is an arm 9| on whose. free end a feeding pawl 98 is fulcrumed. A lever 92 and a link 92a connect the tail of this pawl to the chuck-control lever 33.

The mechanism which is influenced by the length of the stock, and places the timing mechanism 8|, etc., in active position, will now be described with reference to Figs. 6 and 7.

Fulcrumed on the annular table I88 at diametrically opposite points I85 and I86 are bellcranks I83 and I84 whose longer arms are connected to springs I81 and I88, holding them against bars I8I and I82, respectively, which descend from two tubes 2 of the stock reel through holes in the table I88. The shorter arms of the bellcranks are connected by a rod I89 which is pivotally connected to the bellcrank I84 and engages the bellcrank I83 with a slotted eye II8. A bolt H2 is fulcrumed below the table I88 at II 2a. Its upper end is engaged by a slot in the bellcrank I84 and its lower end II3 bears against a lug- I I4 on the retaining pawl 81, holding its tooth 86 beyond reach of the teeth of the ratchet wheel 8| while the'bellcranks I83 and I84 are in their full-lines position, i. 'e., are retained by the bars I8I and I82against the action of their springs I81 and I88.

The operation of this machine is as follows:

The stock reel is filled with bar stock by lifting its tubes 2 from the holes 24a in the base plate 28, moving their lower ends away from the shaft I of the stock reel-which is permitted by some clearance in the holes 24 of the upper plate 2I-- inserting a bar in each tube, and returning the tubes into their holes 24a with their lower ends. The lower ends of the bars are supported by the flaps 28. The stock reel turns in the direction of the arrow in Fig. 4 under the action of the weight 13 when released by the detent 16. When two diametrally opposite tubes arrive in that echanism. A shaft 8Ia is mount-' in the connecting rod 31.

position'in which their flaps are opened by the checks 3|, the bars .in' the tubes are dropped through the holes 21 and into the hollow unit shafts 3 and 3'. The chucks I9 and 19' are opened by the crank pins 38 and 38' and the the cable 48, turning the crank 41 and the forkanti-clockwise. By these means, the chucks I9 are opened and closed periodically. Since the fulcrum 34 of the chucking lever 33 is supported by the spring 35, a certain yield is provided for so that the chucks I9, I9 are not damaged if stock of too large diameter is supplied.

The carriage 1 is reciprocated by the cam 6| and, on its quick return, asdescribed, couples the shaft 42 to the bevel gear42, the shaft performs one revolution and the clutch I9 is opened, allowing the bar to descend by gravity until it is intercepted by the inner end of the slide 32. When the chuck has been opened for the second time, the bar is presented to the cutter 8 which now, upon the second advance of the carriage I, trims and shapes the lower end of the bar. The part which is removed in this way is but a few millimetres long and by the trimming the deformation caused by the shearing of the stock at the mill, is removed. Upon the second return of the carriage 1, the'shaft 42'. is again coupled tothe bevel gear 42. In the meantime, the slide 32 has been withdrawn by the pawl 5|, and the bar now descends as far as the mandrel I8a bywhich it. is elastically arrested under the action of the spring I2, the mandrel being then in its elevated position under'the action of the eccentric portion 68 at. the cam I4. The chuck I9 is now closed again, and a piece of the prescribed length is cut from the bar by the cutter 8 which new advances again with the slide I. When the comparatively heavy bar strikes the mandrel, it is thrown back by the reaction of the spring I2, and then assumes the proper position. The lag required for this is provided for by the slot 39 The first operation is now completed, and the severed pieces from both bars are delivered to the collectors I50 and As the chucking lever 33 oscillates, the feeding pawl 9 is reciprocated but only turns the timing ratchet wheel 8| idly while a bar is still partly in the corresponding tube 2 of the stock reel, and partly in the corresponding unit shaft 3, 3', While this condition lasts, the bars I8I and I82 hold the bellcranks I83 and I84 in the full-lines position of Fig.. 7 against the action of the springs I81 and I88. But when the upper end of each bar has left the cage altogether after the bar has been finished, the springs throw the end of the bellcrank I84 and its lower end I I3 releases the lug I I4 on the retaining pawl 81 so that the spring 81a now urges the tooth 86 of the pawl into the gaps between the teeth of the timing v be turned against the arrow 9 since the flanks ear wheel 8! under-the resilient pressure of the Spring 87a, allowing the timing gear wheel 8| to of its teeth slope atthe corresponding side. The feeding pawl 98 now takes action on the gear wheel and,turns it against the arrow 1) and the action of the weight 85. Each, operation of the feeding pawl corresponds to one operation of the cutters 8 and 8 on the bar, i. e., every time a piece is detached. When the timing gear wheel has performed a certain number of partial revolutions-as determined by the adjustment of the lug 80,this lug engages the hook 19 at the end of the detent 76, causing the tooth 18 to re lease the indexing disk 18 at the tooth 15 it had engaged so that the weight 13 turns the cage in.

the direction .of the arrow in Fig. 4 until the detent engages the next tooth l5 and arrests the stock reel in a position in which two freshbars are presented to the hollow shafts 3 and 3'. When the detent i8 is turned to make its tooth 75 clear the indexing disk M, the crooked arm 16 of the detent depresses the tail of the retaining pawl 81, disengaging its tooth 86 from the teeth of the timing gear 8|, and allowing the weight 85 to turn the gear in the direction of the arrow p. When the fresh bars have been liberated "by the flaps .28, as described, they return the bellcranks I83 and I84 into their initial position, full lines in Fig. '7, and the retaining pawl 81 is again thrown out by the bolt H2.

When the retaining pawl 81 ismoved into its active position after havingbeen released by-the bolt H2, it elevates the rod 89 by means of the abutment 88 so that its end engages between the teeth 75 of the indexing plate 18. During the indexing of the stock re'el, the rod 89 is depressed for a short time by the engagement of its beveled upperend with the beveled flange 15' of the correspondingtooth i5, and its pawl 15 releases the slide 32 which is now returned into its inner final position below the chuck 89 byits return spring 55.

When the retaining pawl 87 has released the timing gear, wheel 8!, the weight 85 returns the gear wheel into its initial position in the direction of the arrow 9. In its initial position, a lugnot shown-on the gear wheel bears against a fixed abutment-not shown-under the pressure of the weight 85. By suitable adjustment of the lug 88 on the control gear wheel 8| the number of operations to be performed on the two bars in the units Brand B2, until the stock reel is indexed,

Preferably, an idle step is performed at the end of the cycle, for allowing the remainder of the bar to be removed.

Means are provided for automatically arresting the machine if trouble occurs, or if the supply of bars in the stock reelhas become ex hausted.

When the resistance against the operation of wise by the cam 8i against the action of its spring B6, and the spring 63 is compressed, since the upper arm 53 is restrained by the excessive resistance at the cutter 8 or 8'. The angular arm does not partakein the movement of the lower arin 53a, since it is anchored to the upper arm- 53 at 53?) by the link 94. Therefore, the'lower end of the angular arm to which the slotted link 96 is pivoted, is stationary and. as the lower arm 53a moves clockwise, a contact pin 950, on. the arm engages a contact 95 on the link 96 and, by suitable means, not illustrated, acircuit is operated for cutting out the motor 46'.

Mechanical means might also be provided for arresting the machine. Thus, the link 96 might be weighted and supported on the lower arm 53a by a hook or the like, so that the mix and its weight are dropped upon movement of the lower arm. 1

For arresting the machine when the stock reel is empty, 9. seat for the weight 13 might be provided on which theweight arrives after one half revolution of the stock reel, or a lug on the distributor 26 might be arranged to engage a fixed abutment. In this case the rods 89 and 89' are not depressed and their abutments 88, 88' hold the retaining pawl 81 in such position that its tooth engages between the teeth of the control gear 8|. The gear wheel cannot now be turned in the direction of the arrow 12 and so it is not fed from its initial but from its final position,

and the weight 85 is raised beyond its normal position. It engages one end of a double-armed lever 91 which is fulcrur'ned at 98. A cable 99 for arresting the machine 'is attached to the other end of thedouble-armed lever for arresting the machine by mechanical means. Obviously, contacting means might be provided for the same purpose. I

If the diameter of the bar stock is so small that the chucks l9, l9 are-unable to engage the bars, the latter are not rotated and the effect is the same as in the case of too hard material, etc., as described above, On the other hand, if the stock is too large for the chucks, it cannot move through the open chucks and so the cage cannot be indexed, and the retaining pawls cannot be moved into active position.

Obviously, the machine may be modified in Various ways without departing from my invention. Thus, as mentioned more than two tooling units might be provided, or the machine might be equipped with lathe tools for shaping as well as cutting the bar stock.

In the machine which has been described, the

operation of the control and its timing mechanism is determined by the longest bar in the stock reel, for it will appear from Fig. '7 that the locking pawl H2 is not influenced by bars of shorter length. While this arrangement is generally satisfactory, it has the drawback that the end of a shorter rod which has not the full length of the sections to be severed, is of ir-' regular shape. When it occurs that such an end is presented to a tool 8 or 8', the tool will be damaged.

In the machine which will now be described with reference to Figs. 8 and 9, such accidents are eliminated by arranging for the shortest bar to determine the operation of the control and the timing mechanism.

The machine illustrated in Figs. 8 and 9 is substantially similar to the machine illustrated in Figs. 1' to 7 and therefore it has not been completely shown. It is distinguished only by certain details, as will now be described.

The stock reel is dispensed with and instead of the annular table I08, this machine has only two diametrally opposite small, tables lllfl and lllllb. The bellcrank I83 is arranged on the table 188a as described with reference to Fig. 7 but the mechanism on the table Illlib is modifled. A double-armed lever I I9 is iulcrumed on the table IIIIib at I05, and the spring I98 holds its outer end against the bar I 02.- At Its inner end, the lever has a finger I2I for cooperation with the upper end of the locking bolt 2. In order to operate the locking bolt from the bellcrank I03, the connecting rod I99 (without the slotted eye III!) is pivotally connected to one arm of a bell-' crank I22 also fulcrumed'at I05 and equipped with a finger I at its other arm for engaging the bolt II2. Obviously, the shortest bar will cause the bolt II2 to release the retaining pawl and consequently the beginning of the operation of the control, and its end, are determined by the shortest length of stock.

to the arm I38 of a four-armed clutching lever I25 which is iulcrumed at I3I and equipped with a detent I32 adapted to engage two notches I26 in 'a bracket on the frame A. The lever I25 engages a clutch I21 for connecting the shaft 45a to the gearing I28, In the position illustrated in Fig. 8, the clutch I21 isthrown in, and it is thrown out by turning the lever I25 anti-clockwise. The connection is so designed that the clutch I21 is thrown out when the link 31 is in the position shown in dotted lines in Fig. 8, i. e.,- the machine is arrested when the chucks I9 and I9 are open so that any bar ends which have not dropped out, can be removed by hand.

A-hand wheel I29 is secured on the outer end of the shaft 45a for moving the carriages 1 and 1', the control 8|, and the chucks I9 and I9 by hand independently of the drive of the machine. By turning the hand wheel I29, the lug 80 is moved clear of the hook 19 at the free end of the lever I23 so that this lever, and the clutching lever I25, can be manually returned into that position in which the clutch I21 is thrown in. At the same time, the weight 85 is free to return the control bevel gear BI into its initial position.

This machine may be simplified by providing an upward extension on the retaining pawl 81 which replaces the locking bolt II2. Such an arrangement is particularly suitable for machines having a single tooling unit only, since in this case the extension can be made integral with a member 3 adapted to be engaged by the bar stock, like the bellcrank I03, or the double-armed lever II9, Fig. 9. l

I claim: 4 1. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units, means for adjusting the control for a predetermined number of machining operations on each bar in each unit, and mechanism influenced by the length of the bars for placing the control in active condition.

2. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units, means for adjusting the control for a predetermined number of machining operations on each bar in each unit, mechanism influenced by the length of the bars'for placing the control in active condltion, means for supplying stock to all units, and means operatively connected to the control for the stock-simply! means.

3. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units, means for adjusting the control for a predetermined number of machining operations on each bar, a locking bolt for holding the control in inactive 1 condition, and a spring-actuated lever arranged to be engaged by the bar which is being machined at the time, and to engage the locking bolt under the action of its spring and to release the control, after the bar has moved clear of the lever. 4. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units, means for adjusting the control for a predetermined number of-machining operations on each bar, and a pair of interengaged mechanisms each influenced independently by the length of the bars, for placing the control in active condtion.

5. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a

control operatively connected to all units and-including a timing mechanism, and means for operating the timing mechanism; a pawl for rendering the timing mechanism responsive and mmsponsive to the operating means, automatic means tending to move the pawl into its-re:- sponsive-rendering position, a system arranged to be locked against operation, and to be released for operation, by the bar stock: for holding the pawl in its inresponsive-rendering position when the system is locked, and for releasing the pawl to move into its responsive-rendering position under the action of the said automatic means when the system is released, and automatic means for operating the system after it has been released.

6. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units and in cluding a timing mechanism, and means for operating the timing mechanism; a pawl for rendering the timing mechanism responsive and inresponsive to the operating means, automatic means tending to move the pawl into its responsive-rendering position, abolt for holding the pawl in its inresponsive-rendering position, a. swinging lever arranged at each tooling unit, automatic means for holding each lever against the bar being tooled in the corresponding unit,

means operatively connecting one of the levers to the bolt so that the bolt holds the pawl in its inresponsive-rendering position when the'lever is held against the bar by its automatic means, and

the bolt is moved to-release the pawl when the 'bar has nioved past the lever, and its automatic means has become active; a connecting rod which ispivoted to the bolt-controlling lever atone end, and a slotted eye at the other end of the connecting rod arranged to engage the other lever and to allow it to move independently of the bolt-controlling lever under the action 01' its automatic means.

'1. In a machine tool for the periodical machining of bar stock, a plurality of tooling units, a control operatively connected to all units and including a timing mechanism, and means for operating the timing mechanism; a pawl for rendering the timing mechanism responsive and inresponsive to the operating means, automatic means tending to move fliepawl into its responsive-rendering position, a bolt for holding the pawl in its inresponfiIB-rmdudng position,

aswingingleveran'anaedateachtoolingmiit,

automatic means for holnlngeachlevu'agaii'utj the bar being tooled in the corresponding unit, means operatively connecting one of the levers to the'bolt so that the bolt holds the pawl in its inresponsive-rendering position when the lever is held against the bar by its automatic means, and the bolt is moved to release the pawl when the bar has moved past the lever, and its automatic means has become active; a member arranged to move the bolt-controlling lever only in that direction in which the bolt is moved to release'the pawl, and a connecting rod pivoted to the member at one end,- and to the other lever 5 at its other end.

EUGEN NZ'LDELIN. 

